- ID:
- ivo://CDS.VizieR/J/A+A/658/A21
- Title:
- Infrared-radio relation in the local universe
- Short Name:
- J/A+A/658/A21
- Date:
- 21 Mar 2022 09:38:59
- Publisher:
- CDS
- Description:
- The Square Kilometer Array (SKA) is expected to detect high-redshift galaxies with star formation rates (SFRs) up to two orders of magnitude lower than Herschel surveys and will thus boost the ability of radio astronomy to study extragalactic sources. The tight infrared-radio correlation offers the possibility of using radio emission as a dust-unobscured star formation diagnostic. However, the physics governing the link between radio emission and star formation is poorly understood, and recent studies have pointed to differences in the exact calibration required when radio is to be used as a star formation tracer. We improve the calibration of the relation of the local radio luminosity-SFR and to test whether there are nonlinearities in it. We used a sample of Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) sources and investigated their radio luminosity, which was derived using the NRAO VLA Sky Survey (NVSS) and Faint Images of the Radio Sky at Twenty-cm (FIRST) maps. We stacked the bins of infrared luminosity and SFR and accounted for bins with no detections in the stacked images using survival analysis fitting. This approach was tested using Monte Carlo simulations. After removing sources from the sample that have excess radio emission, which is indicative of nuclear radio activity, we found no deviations from linearity of the mean relations between radio luminosity and either SFR or infrared luminosity. We analyzed the link between radio emission and SFR or infrared luminosity using a local sample of star-forming galaxies without evidence of nuclear radio activity and found no deviations from linearity, although our data are also consistent with the small nonlinearity reported by some recent analyses. The normalizations of these relations are intermediate between those reported by earlier works.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/629/288
- Title:
- Infrared sources near AFGL 5142
- Short Name:
- J/ApJ/629/288
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared JHK' and H_2_ v=1-0 S(1) imaging observations of the star-forming region AFGL 5142 are presented. A cluster of young stars is confirmed to be embedded in the dense molecular cloud core. Many point sources are newly detected. The cluster's K'-magnitude distribution and [H-K'] color peak have brighter and redder magnitudes than those outside the cluster. Many of the cluster sources exhibit infrared excesses typical of T Tauri stars, Herbig Ae/Be stars, and protostars. The observations also reveal new H_2_ line emission around the cluster, exhibiting several jets, filaments, and a faint elliptical structure. The jets are associated with the CO outflows in the region. The powering sources of the jets, the CO outflows, and the small faint elliptical structure are identified and analyzed individually. The strong H_2_ jets and faint diffuse emission further confirm that the cluster is in an early stage of evolution.
- ID:
- ivo://CDS.VizieR/J/PASP/115/351
- Title:
- Infrared Southern Cool Carbon Stars
- Short Name:
- J/PASP/115/351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A large set of deep, near-IR, objective-prism plates taken along the southern Galactic plane was searched for cool supergiants and carbon stars. Accurate coordinates and charts for 759 carbon stars in two Galactic longitude sectors within 7.5{deg} of the plane, 248{deg}<l<288{deg} and 320{deg}<l<341{deg}, are given, including 289 stars not previously published. Many of the new and known stars are found in the IRAS, DENIS, and 2MASS point-source catalogs. The 2MASS colors and the longitude distribution of cool carbon stars are discussed briefly.
- ID:
- ivo://CDS.VizieR/J/MNRAS/374/399
- Title:
- Infrared star clusters with |b|<20{deg}
- Short Name:
- J/MNRAS/374/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used star density maps obtained from the Two-Micron All-Sky Survey (2MASS) to obtain a sample of star clusters in the entire Galactic Plane with |b|<20{deg}. A total of 1788 star cluster candidates are identified in this survey. Among those are 681 previously known open clusters and 86 globular clusters. A statistical analysis indicates that our sample of 1021 new cluster candidates has a contamination of about 50 per cent. Star cluster parameters are obtained by fitting a King profile to the star density. These parameters are used to statistically identify probable new globular cluster candidates in our sample. A detailed investigation of the projected distribution of star clusters in the Galaxy demonstrates that they show a clear tendency to cluster on spatial scales in the order of 12-25pc, a typical size for molecular clouds.
- ID:
- ivo://CDS.VizieR/J/A+A/463/175
- Title:
- Infrared study of IRAS 14416-5937 region
- Short Name:
- J/A+A/463/175
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out an infrared study of the southern Galactic massive star-forming region associated with IRAS 14416-5937. This star-forming region has been mapped simultaneously in two far infrared bands at ~150 & 210 micron using the TIFR 1-m balloon borne telescope with ~1' angular resolution. We have used the 2MASS JHKs data as well as the GLIMPSE-Spitzer data of this region to study the stellar populations of the embedded young cluster. This region comprises of two sources designated as A and B, separated by ~2pc. The spectrum of a region located close to the source A obtained using the Long Wavelength Spectrometer (LWS) on-board the Infrared Space Observatory (ISO) is presented. Emission from warm dust and the unidentified infrared bands (UIBs) is estimated using the mid-infrared data from the MSX survey. The spatial distribution of the temperature of cool dust and optical depth at 200 micron have been obtained taking advantage of the similar beams in the two TIFR bands. A number of atomic fine structure lines have been detected in the ISO-LWS spectrum, which have been used to estimate the electron density and the effective temperature of the ionising radiation in this region. From the near and mid infrared images, we identify a dust lane due north-west direction of the source A. The dust lane is populated by Class I type sources. Class II type sources are found further along the dust lane as well as below it. Self consistent radiative transfer models of the two sources (A and B) are in good agreement with the observed spectral energy distributions. The spatial distribution of young stellar objects in and around the dust lane suggests that active star formation is taking place along the dust lane and is possibly triggered by the expanding HII regions of A and B.
- ID:
- ivo://CDS.VizieR/J/AJ/134/214
- Title:
- Infrared study of J-type carbon stars
- Short Name:
- J/AJ/134/214
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We collected 113 J-type carbon stars from the published literature. Observations from 2MASS, IRAS, and ISO show that, except for silicate carbon stars in the J-type carbon star domain, the infrared properties of the other J-type carbon stars are quite similar to those of ordinary carbon stars. The above results imply that the chemical peculiarity of enhanced ^13^C for J-type carbon stars is not reflected in the infrared region. In addition, the possible evolutionary scenario and binarity for J-type carbon stars are also discussed.
- ID:
- ivo://CDS.VizieR/J/AJ/140/462
- Title:
- Intermediate-mass star-forming regions
- Short Name:
- J/AJ/140/462
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In an effort to understand the factors that govern the transition from low- to high-mass star formation, for the first time we identify a sample of intermediate-mass star-forming regions (IM SFRs) where stars up to (but not exceeding) ~8M_{sun}_ are being produced. We use IRAS colors and Spitzer Space Telescope mid-IR images, in conjunction with millimeter continuum and ^13^CO maps, to compile a sample of 50 IM SFRs in the inner Galaxy. These are likely to be precursors to Herbig AeBe stars and their associated clusters of low-mass stars.
- ID:
- ivo://CDS.VizieR/J/A+A/349/L69
- Title:
- Interstellar extinction
- Short Name:
- J/A+A/349/L69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- DENIS observations in the J(1.25{mu}m) and K_S_(2.15{mu}m) bands together with isochrones calculated for the RGB and AGB phase are used to draw an extinction map of the inner Galactic Bulge. The uncertainty in this method is mainly limited by the optical depth of the Bulge itself. A comparison with fields of known extinction shows a very good agreement. We present an extinction map for the inner Galactic Bulge (~20{deg}^2^)
- ID:
- ivo://CDS.VizieR/J/A+AS/132/211
- Title:
- Interstellar SiO sources
- Short Name:
- J/A+AS/132/211
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a survey of SiO emission using the 15-m SEST and the 20-m Onsala telescope are presented in two tables. The sample contains altogether 369 objects including 270 H2O masers, 19 OH masers and 62 IRAS sources with colours typical for ultracompact HII regions. The remaining target sources consist of dust continuum peaks a CS emission peak near H2O masers (12) and Herbig-Haro objects (6). The entries are arranged according to increasing right ascension.
- ID:
- ivo://CDS.VizieR/J/ApJ/841/76
- Title:
- Intrinsic far-IR SED of luminous AGNs
- Short Name:
- J/ApJ/841/76
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The range of currently proposed active galactic nucleus (AGN) far-infrared templates results in uncertainties in retrieving host galaxy information from infrared observations and also undermines constraints on the outer part of the AGN torus. We discuss how to test and reconcile these templates. Physically, the fraction of the intrinsic AGN IR-processed luminosity compared with that from the central engine should be consistent with the dust-covering factor. In addition, besides reproducing the composite spectral energy distributions (SEDs) of quasars, a correct AGN IR template combined with an accurate library of star-forming galaxy templates should be able to reproduce the IR properties of the host galaxies, such as the luminosity-dependent SED shapes and aromatic feature strengths. We develop tests based on these expected behaviors and find that the shape of the AGN intrinsic far-IR emission drops off rapidly starting at ~20{mu}m and can be matched by an Elvis+ (1994, J/ApJS/95/1)-like template with a minor modification. Despite the variations in the near- to mid-IR bands, AGNs in quasars and Seyfert galaxies have remarkably similar intrinsic far-IR SEDs at {lambda}~20-100{mu}m, suggesting a similar emission character of the outermost region of the circumnuclear torus. The variations of the intrinsic AGN IR SEDs among the type-1 quasar population can be explained by the changing relative strengths of four major dust components with similar characteristic temperatures, and there is evidence for compact AGN-heated dusty structures at sub-kiloparsec scales in the far-IR.
